Coming of Age in the Milky Way (27 page)

In retrospect all is clear, and veins of scientific genius may be
found running through the musings of the young Einstein. He had been a quietly religious child, who at the age of eleven composed little hymns in honor of God that he sang on his way to school. But at about age twelve, as he recalled many years later, he

Einstein later saw this conversion, from traditional religion to what he called his “holy” Euclid text, as involving two ways of striving for the same deliverance:

Even Einstein’s lack of precocity looked in hindsight like a gift in disguise. Einstein felt that he had “developed so slowly that I only began to wonder about space and time when I was already grown up. In consequence I probed deeper into the problem than an ordinary child would have done.” Whatever the cause, he certainly possessed unusual powers of concentration: Like Newton, who credited his insights into deep problems to his habit of “thinking of them without ceasing,” Einstein was implacably tenacious
in pursuing a line of thought once it had captured his attention.
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And, like Galileo, he combined a taste for fundamental philosophical questions with an appreciation of the importance of testing his ideas empirically: “Direct observation of facts,” he said, “has always had for me a kind of magical attraction.”
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The intellectual odyssey that led Einstein to the special theory of relativity—and from there to the general theory, which was to deliver theoretical cosmology from its infancy—began when he was no more than five years old. He was sick in bed, and his father showed him a pocket compass to keep him amused. He asked what made the compass needle point north, and was told that the earth is enshrouded in a magnetic field to which the needle responds. He was astonished. It seemed, he recalled many years later, “a miracle” that an invisible, intangible field could govern the behavior of the very real compass needle. “Something deeply hidden,” he thought, “had to be behind things.”
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He learned what that something might be a few years later, when he read a textbook description of James Clerk Maxwell’s theory of the electromagnetic field. Maxwell had built his field theory on the experimental work of the English scientist Michael Faraday. The two men, as Einstein later noted, were related to each other much as were Galileo and Newton—“the former of each pair grasping the relations intuitively, and the second one formulating those relations exactly and applying them quantitatively.”
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Faraday, a blacksmith’s son, had been an apprentice to a London bookbinder. He read popular-science books in his spare time, and when a friend took him to hear a series of public lectures by the chemist Sir Humphry Davy, Faraday took notes on the lectures, printed them, bound them in leather, and sent them to Davy, who responded by hiring him as a laboratory assistant at the Royal Institution of Great Britain. There Faraday remained for the next
forty-six years, eventually succeeding Davy as the institution director. He was an Edisonian figure, his white hair parted in the middle over wide-set eyes and slab-flat cheekbones, his shoulders stooped with work and his large hands buried in laboratory apparatus, though he smiled as habitually as Edison scowled.

In the course of more than fifteen thousand experiments, Faraday found that electricity and magnetism are conveyed by means of invisible lines of force arrayed in space—i.e., by fields. (Students today who sprinkle iron filings on a paper resting on a horseshoe magnet to watch the filings trace out the magnetic field lines are replicating an old Faraday experiment.) His gift to science amounted to a fundamental shift in emphasis, from the visible apparatus, the magnet or electrical coil, to the invisible field that surrounds it and conveys the electrical or magnetic force. Here began field theory, which today explores processes ranging from the subatomic to the intergalactic scale and portrays the entire material world as but a grand illusion, spun on the loom of the force fields. Einstein was to be its Bach.

But though Faraday established the existence of electrical and magnetic fields, he lacked the mathematical acumen required to write a quantitative description of them. This was left for Maxwell. Thin-boned as a bird, with trusting, farsighted eyes and a choirboy’s fragile countenance, Maxwell was at home in mathematical castles inaccessible to Faraday. A methodical thinker, he first studied electricity and magnetism by reading Faraday’s papers—this on Lord Kelvin’s advice, in order to introduce himself to the fields through Faraday’s eyes—and only thereafter subjected them to the arc lamp of his mathematical skills. The result, Maxwell wrote Kelvin in 1854, was to “have been rewarded of late by finding the whole mass of confusion beginning to clear up under the influence of a few simple ideas.”
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This was the beginning of the abstraction of the field concept, a step that would spell the end of purely mechanistic science and lead to the nonvisualizable but far more flexible mathematical flights of relativity and quantum physics. Faraday read the papers Maxwell sent him with the bemusement of a tone-deaf man listening to Beethoven’s quartets, understanding that they were beautiful without being able to appreciate just how. “I was almost frightened when I saw such mathematical force made to bear upon the subject, and then wondered to see that the subject stood it so well,” Faraday
wrote Maxwell. In another letter he asked, touchingly and tentatively:

Maxwell obligingly rendered some of his explanations of field theory into the mechanical cogwheels and sprocket formulations that Faraday could understand, but it was when stripped to bare equations that his theory flew. With fuguelike balance and power, Maxwell’s equations demonstrated that electricity and magnetism are aspects of a single force, electromagnetism, and that light itself is a variety of this force.
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Thus were united what had been the separate studies of electricity, magnetism, and optics.

When the young Einstein encountered Maxwell’s equations they struck him, he said, “like a revelation.” Here was a precise and symmetrical account of the invisible field that governed the compass needle. It animated space, could “weave a web across the sky” as Maxwell had put it, and its differential equations etched the outlines of that web with exquisite balance and precision.

“What made this theory appear revolutionary,” Einstein recalled, “was the transition from forces at a distance to fields as fundamental variables.”
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It was no longer necessary to invoke the idea of an aether transmitting light across space; the electromagnetic field in itself could do the job. This had not been appreciated by the older, classical physicists, Maxwell himself among them. Theirs was a putatively hardheaded, mechanical world view, in which the
fields taken by themselves appeared too insubstantial to be real. It was by their consensus that the aether hypothesis had glided on, a ghost ship alive with Saint Elmo’s fire, well after Maxwell’s equations and the Michelson-Morley experiment had emptied the wind from its sails. Einstein, caring little for tradition, abandoned the aether and focused his attention on the field.

Yet if one adhered to both Maxwell’s equations and Newton’s absolute space, the result was a paradox. This the giants of physics understood; it was one of their reasons for underestimating the importance of Maxwell’s field equations. Einstein, ignorant of their wisdom, discovered the paradox for himself, at the age of sixteen. He was at the time enrolled in a preparatory school at Aarau, in the Swiss Oberland, where he enjoyed taking walks along the river oxbows. (Years later he would write a paper defining how rivers meander.) One day, Einstein asked himself what he would see if he were to chase a beam of light at the velocity of light. The answer, according to classical physics, was that “I should observe such a beam of light as a spatially oscillatory electromagnetic field at rest. However, there seems to be no such thing, whether on the basis of experience or according to Maxwell’s equations.”
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Velocity was inherent to light; it was, after all, by way of its velocity that light had revealed to Maxwell its identity as an electromagnetic field. Yet if we live in an absolute, Newtonian space demarcated by the aether, it should be possible to catch up with a light beam and thus rob it of its speed. Something had to give, in either Newton’s physics or Maxwell’s.

Einstein was acquainted with another electrodynamic paradox as well, one that had turned up literally in his own backyard, in the iron and copper dynamos that his father and his uncle Jakob had built in an electrical shop behind the family home in the Munich suburbs. The principle of the dynamo, established by Faraday, was that the field created by a whirling magnet will generate an electrical current in a surrounding web of wire. This finding had tremendous practical potential: The energy of a steam engine or a flowing stream could be harnessed to produce electricity that could then be exported via electrical lines to power machinery and illuminate city streets miles away. Although the Einstein family never managed to make much of a living from it, dynamo design was on the forefront of contemporary technology, and giant steam-driven dynamos
were being commissioned and built at considerable expense.
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Yet their performance could not be predicted with exactitude so long as the behavior of the electromagnetic field within the dynamo was so poorly understood. Under existing theory, the moving field was to be explained according to one set of rules if viewed from the perspective of a dynamo’s rotating magnet, and another if viewed from the stationary electrical coil. Every dynamo housed a whirling mystery.

The situation was economically embarrassing for the industrialists. It bothered Einstein as unaesthetic. “The thought that one is dealing here with two fundamentally different cases was for me unbearable,” he recalled. “The difference between these two cases could not be a real difference but rather, in my conviction, only a difference in the choice of the reference point.”
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Such questions were still on Einstein’s mind when he completed his year of preparatory school, but if he hoped to find guidance in solving them at the Polytechnic Institute, he was soon disappointed. His physics professor, the capable but conservative Heinrich Friedrich Weber, was fascinated by dynamos, owed his chair to the philanthropy of the dynamo builder Werner von Siemens, and was sufficiently devoted to the study of electricity that he repeatedly submitted himself to electrical shocks of one thousand volts and more of alternating current—this as part of an effort to determine how much voltage a human being could endure.
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Yet Weber, steeped in the traditions of classical physics, never lectured
on Maxwell or Faraday. Einstein soon lost interest and started cutting Herr Weber’s classes. He read physics on his own and conducted experiments in the Polytechnic’s superb laboratories. One of his experiments resulted in an explosion that badly injured Einstein’s hand and nearly wrecked the lab.

Professor Weber responded by doing what he could—which was a great deal—to prevent Einstein’s getting a job after graduation. Thus stigmatized, Einstein went nowhere. The distasteful experience of cramming for the comprehensive final examinations had in any event left him unable to think about science for a full year, and he spent his time reading philosophy and playing the violin. When he did resume the study of physics, it was with little encouragement from the outside world. He submitted a thesis on the kinetics of gases to the University of Zurich, but no doctorate was forthcoming. He wrote a few scientific papers, but they were almost worthless. And yet, though regretting that he was a disappointment to his parents, Einstein remained serenely self-confident. “I have a few splendid ideas,” he wrote to his friend Marcel Grossmann, “which now only need proper incubation.”
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It was with the help of Grossman’s father that Einstein got the patent office job, and while we may shake our heads at the spectacle of so great a man in so slight a position, Einstein remembered it as “my best time of all.”
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He enjoyed contemplating the mechanical gadgets that came before him for review, found that writing critiques of patent applications helped him learn to express himself succinctly, and reveled in the companionship of his friend Michele Angelo Besse, with whom he discussed philosophy, physics, and everything under the sun. “I could not have found a better sounding-board in all of Europe,” he said.
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